Meet the Team

Michael Glotzbecker, MD

Chief, Pediatric Orthopaedics
Associate Surgeon-in-Chief, UH Rainbow Babies & Children's Hospital

Dr. Glotzbecker joined the UH Rainbow team as Division Chief in September 2019 after being in practice in Boston for the previous 10 years. He received his undergraduate degree at Duke University and completed medical school at the University of Pennsylvania School of Medicine. His residency training was completed at the Harvard Combined Orthopaedic Residency Program and he completed his fellowship at Boston Children’s Hospital.

He has interests in scoliosis and other complex spinal conditions, pediatric trauma and fracture care as well as general pediatric orthopedics. He is active in international study groups including the Pediatric Spine Study Group (Treasurer), where he previously served as chair and is an active member in the Harms Study Group. He is past chair of the Quality and Safety Committee of the Scoliosis Research Society and current chair of the Spine Quality & Safety Value Committee for the Pediatric Orthopaedic Society of North America (POSNA).

He currently is the Associate/Acting Surgeon-in-Chief for UH Rainbow and is hospital lead for the Surgical Site Infection Clinical Effectiveness Team. Additionally, he is participating in the MBA program at Weatherhead School of Management at Case Western Reserve University with expected graduation in May 2025.

His wife, Brett, is Chief Medical Officer of the UH Academic Market. His twins, now 10, love to swim and ski. They also play soccer and lacrosse. They are big fans of Harry Potter and Taylor Swift and the entire family was able to see Taylor Swift in concert in October. They have a Portuguese water dog, Isla, and shitzu/poodle, Dolce.

Contact: Michael.Glotzbecker@UHhospitals.org

Allison Gilmore, MD

Dr. Gilmore, a life-long Clevelander, obtained her undergraduate and master’s degrees in exercise science at Ohio State University and Cleveland State University. She obtained her medical degree from Case Western Reserve University School of Medicine. She completed her residency in orthopedic surgery at Mount Sinai Medical Center in Cleveland and subsequent fellowship in pediatric orthopedic surgery at UH Rainbow Babies & Children’s Hospital and has been a practicing pediatric orthopedic surgeon at UH Rainbow since graduation. Dr. Gilmore has expertise in the evaluation of the full-spectrum of general pediatric orthopedic conditions and has a special interest in pediatric surgical sports medicine.

Dr. Gilmore lives in Shaker Heights with her husband Michael, an attorney, and son Bailey. In her spare time she enjoys running and weight lifting

Contact: Allison.Gilmore@UHhospitals.org

Christina Hardesty, MD

Dr. Hardesty was raised near Sacramento, California, and obtained her undergraduate degree in biology and math at Hendrix College. She attended medical school and completed an orthopedic surgery residency at the University of Arkansas for Medical Sciences. She completed a fellowship in pediatric orthopedic surgery at UH Rainbow Babies & Children's Hospital and a secondary fellowship in neuromuscular orthopedic Surgery at A.I. DuPont Hospital for Children. Dr. Hardesty’s clinical interests include pediatric spine deformity (such as scoliosis), baclofen pumps, cerebral palsy, spina bifida, spinal muscular atrophy and other neuromuscular disorders. She is the leader of the Graduates Research Interest Group of the Pediatric Spine Study Group, chair elect of the Education Resource Committee of the Scoliosis Research Society, on the Board of Directors of the Spasticity Treatment and Research Society, and the board president of Youth Challenge in Cleveland. In her spare time, she is an Orangetheory addict, bakes a lot, and sometimes flies airplanes. She and her husband, Dustin, have two boys, Jack and Henry. They keep her on her toes.

Contact: Christina.Hardesty@UHhospitals.org

Katharine Hollnagel, MD

Dr. Katharine Hollnagel is the most recent addition to the UH Rainbow team.  She is a Northeast Ohio native who was born in Akron, Ohio and raised in Hudson, Ohio. She received her undergraduate degree from Colgate University and completed medical school at the Virginia Tech Carilion School of Medicine.  She completed her orthopedic surgery residency training at the University of Toledo Medical Center in Toledo, Ohio.  Following residency, she completed fellowships in Pediatric Orthopedic Surgery at Rady Children’s Hospital in San Diego, California, where she was selected the Lena Sefton Clark Fellow, and Pediatric and Young Adult Hip Preservation Surgery from Boston Children’s Hospital in Boston, Massachusetts. Her clinical interests include developmental dysplasia of the hip, femoroacetabular impingement, Legg-Calve-Perthes disease, slipped capital femoral epiphysis (SCFE), and other complex hip deformities as well as orthopedic trauma. Her husband, Dr. Zane Giffen, is a general urologist practicing in Northeast Ohio, and in their free time they enjoy golf, tennis, and hiking with their rescue dog, Mira and most of all time with their son William.

Contact: Katharine.Hollnagel@UHhospitals.org

Raymond Liu, MD

Dr. Raymond Liu was raised in San Dimas, California, and obtained his degree in bioengineering at the University of California, San Diego. After medical school at Johns Hopkins University School of Medicine, he completed an orthopaedic surgery residency at Case Western Reserve University (CWRU). He returned to San Diego for his pediatric orthopaedic surgery fellowship, followed by a mini-fellowship at the Paley Advanced Limb Lengthening Institute in West Palm Beach, Florida. He is the Victor M. Goldberg Professor of Orthopaedics, Case Western Reserve University School of Medicine, with a specialization in complex limb deformity. He is the Past President of the Limb Lengthening and Reconstruction Society and Deputy Editor for Hip and Lower Extremity, Journal of Pediatric Orthopaedics. He enjoys running and spending time with his family.

Contact: Raymond.Liu@UHhospitals.org

R. Justin Mistovich, MD

A northeast Ohio native, Dr. Justin Mistovich grew up in Youngstown. He completed an orthopaedic residency at Allegheny General Hospital in Pittsburgh, followed by fellowship at the Children's Hospital of Philadelphia. He was also selected for a Traveling Fellowship by the Pediatric Orthopaedic Society of North America. His research and clinical interests include sports medicine and the care of the growing athlete, scoliosis, and the optimal management of pediatric and adolescent fractures. He currently serves as a Director of the Pediatric Research in Sports Medicine Society. At Rainbow, he serves as the Fellowship Program Director, and also serves as the Division Director of Pediatric Orthopaedics at MetroHealth. Dr. Mistovich and his wife Keili, a pediatrician, live in Cleveland Heights with Madeleine, their daughter, and Frank, their Vizsla. In their free time, they enjoy sailing and all things Lake Erie, old wooden boats and old home restoration, reading, and tennis.

Contact: Justin.Mistovich@UHhospitals.org

Jochen Son-Hing, MD

Dr. Son-Hing was raised in Vancouver, Canada, and obtained his undergraduate degree in biology at McGill University in Montréal. He then returned to his hometown for medical school and a subsequent residency in orthopedic surgery at the University of British Columbia. He pursued a fellowship in pediatric orthopedic surgery at UH Rainbow Babies & Children's Hospital under the leadership of Dr. George Thompson. He was then a Visiting Scholar in spine surgery at Washington University in St. Louis, under the direction of Dr. Lawrence Lenke. He is skilled in the evaluation of the full spectrum of general pediatric orthopedic conditions and has a special interest in pediatric spine deformity like scoliosis, as well as the care of acute fractures and their long-term sequelae. His wife is a registered nurse and native Northeast Ohioan. They have three children.

Contact: Jochen.Hon-Sing@UHhospitals.org

Michelle Calabretta, MSN, APRN, CPNP

Special Interests: Pediatric fractures, acute injuries, sports medicine, general orthopaedics

Michelle is a pediatric nurse practitioner who has been with our department since 2015. She previously worked in the UH Rainbow Emergency Room as a RN prior to joining our team. She partners primarily with Drs. Gilmore and Hardesty. She sees patients with fractures, acute injuries, and sports-related injuries through our same-day walk-in clinics, as well as helps to coordinate care for our sports medicine and arthroscopic surgery patients. In her free time, she enjoys spending time with her husband and two young children. 

Emily Canitia, CNP

Special Interests: Pediatric fractures, limb deficiencies, hip preservation

Emily is one of our pediatric nurse practitioners and has been with the department since 2015. She partners primarily with Drs. Liu and Hollnagel. She sees patients through our walk-in clinics with general orthopedic injuries and issues and assists with our pediatric limb deformity and lengthening and hip deformity patients. Emily and her husband have three young and busy children and an energetic Australian shepherd.

Michelle Janas MSN, RN, CPN

Special Interests: Scoliosis, neuromuscular deformities, general orthopaedics

Michelle is one of our advanced clinical nurse specialists and has been with our department for nine years. She specializes in scoliosis, cerebral palsy, and tone management. She primarily partners with Drs. Hardesty, Liu, Hollnagel and Gilmore.  She helps to manage and coordinate idiopathic, congenital and neuromuscular spinal deformity patients, intrathecal baclofen pump management, pediatric hip deformity as well as general orthopedics. Michelle and her husband have four children and four grandchildren as well as a labradoodle and red heeler. In her free time she like to travel, hike and bake.

Michelle Moran, BSN, RN, CPN

Special Interests: Scoliosis, spine disorders, general orthopaedics

Michelle has been a nurse at UH Rainbow Babies & Children’s Hospital for more than 29 years. She worked on the surgical trauma floor for 14 years before joining the pediatric orthopedics team. Michelle was selected as a 2024 UH Distinguished Nurse awardee. She primarily partners with Drs. Glotzbecker, Son-Hing, and Mistovich. Michelle enjoys working as an advanced clinical nurse coordinating care while providing support and education to families. Michelle and her husband have three college-age sons and she enjoys playing pickle ball.

Nadine Raile, MS, PA-C

Special Interests: Pediatric fractures, limb deficiencies, hip preservation

Nadine is a physician assistant with the Department of Pediatric Orthopedic Surgery at University Hospitals Rainbow Babies & Children’s. She has been working as a PA in orthopedic surgery for 8 years. Prior to her time at UH Rainbow, she worked in Minnesota at Hennepin County Medical Center in orthopedic trauma and sports surgery. She then relocated to New Jersey, where she worked at Hackensack University Medical Center in pediatric orthopedic surgery. She later relocated to Philadelphia where she worked at Penn Medicine in Hip Preservation and Shriners Children’s, in pediatric orthopedic surgery.

Nadine works primarily at our pediatric injury clinics and also partners with our lower extremity surgeons to coordinate care for pediatric patients with limb and hip deformities. Nadine enjoys spending time with her husband and daughter, traveling, and staying active.

Abigail (Abby) Schlosser, BSN, RN

Special Interests: Scoliosis, spine disorders, general orthopaedics

Abby joined the team two years ago as the research nurse. She actively manages our spinal deformity database, Harms Study Group and PSSG. She is involved in every aspect of the research process including study setup, regulatory compliance and data management. Outside of work, Abby loves spending time outside with her husband and their two children, along with their beloved chocolate lab Charlie.

Nicole (Nikki) Sharp, MSN, APRN, CPNP

Special Interests: Scoliosis, spine disorders, general orthopaedics

Nikki has been at UH Rainbow Babies & Children’s Hospital for over 18 years. She worked as a bedside nurse on the medical-surgical floor, then became a pediatric nurse practitioner in 2013  with the Pediatric Comprehensive Care team prior to joining our department. She brings her vast knowledge of complex pediatric medical care to her role in pediatric orthopedics. She cares for patients with spinal deformities as well as general pediatric fractures and other orthopedic issues. She partners primarily with Drs. Glotzbecker, Son-Hing and Mistovich, but also sees patients independently. In her free time, she enjoys spending time with her family and her golden doodle.